Changliang Xu

Leonurine ameliorates kidney fibrosis via suppressing TGF-β and NF-κB signaling pathway in UUO mice

Fibrosis is one of the characteristic features of chronic kidney disease (CKD). Inflammatory reactions and oxidative stress are implicated in the pathogenesis of fibrosis of CKD. Leonurine (LEO) is one of the active compounds from Herba leonuri. In this study, we further evaluated its renoprotective effect in a mouse unilateral urethral obstruction (UUO), featuring the renal tubulointerstitial fibrosis and inflammation. In this model, pretreat of LEO before ureteral obstruction abolished the expression of fibronectin, suppressed the expression of α-SMA and type I/III collagen and down-regulated vimentin. LEO also modified the cytokine expression of TGF-β, TNF-α, IL-6 and IL-1β and suppressed the phosphorylation of Smad3. Moreover, LEO blocked phosphorylation of NF-κB, and inactivated the signaling pathways associated with the progression of kidney inflammatory response. Our data support that LEO is a candidate renoprotective compound for renal fibrosis through targeting the TGF-β/Smad3 and NF-κB pathway.

Longikaurin E induces apoptosis of pancreatic cancer cells via modulation of the p38 and PI3K/AKT pathways by ROS

Pancreatic cancer is a devastating disease with a poor prognosis. It ranks as the fourth or fifth most common cancer in men and women and has the lowest 5-year survival rate. Therefore, there is an urgent need to develop novel therapeutic agents for pancreatic cancer. Longikaurin E (LE), which is derived from the traditional herbal medicine Rabdosia longituba, had been reported to have anti-proliferative and pro-apoptotic properties in several types of cancers. In this study, we investigated the cytotoxic properties of LE against pancreatic cancer cells and explored the mechanism behind the observed apoptosis. Pancreatic cancer cell lines cultured in the presence of LE exhibited dose- and time-dependent growth suppression by clone formation, methylthiazoltetrazolium assay, lactate dehydrogenase cytotoxicity assay, and fluorescence-activated cell sorting analysis, respectively. In addition, these culture conditions also induced the generation of cellular reactive oxygen species (ROS). In order to determine the mechanisms underlying LE-induced cytotoxicity, we used reverse transcription polymerase chain reaction and Western blot analysis in the pancreatic cancer cell line PANC1. The results showed that the expression of Bax was noticeably upregulated and the expression levels of Bcl-2, Bcl-XL, survivin, and c-Myc were significantly downregulated. We also observed increased p38 phosphorylation and decreased phosphorylation of the PI3K/AKT pathway. Interestingly, we also found that LE activated caspase-3. However, N-acetyl-l-cysteine, a kind of antioxidant, reversed all of these cellular activities. In conclusion, this study suggested that LE induced apoptosis of pancreatic cancer cells via ROS generation to modulate the p38 and PI3K/AKT pathways and could be a promising anti-pancreatic agent.

α-Hederin inhibits interleukin 6-induced epithelial-to-mesenchymal transition associated with disruption of JAK2/STAT3 signaling in colon cancer cells

Colon cancer is the third most frequently diagnosed malignancy and has high morbidity worldwide. Epithelial-mesenchymal transition (EMT) has been increasingly implicated in colon cancer progression and metastasis. The present study was aimed to evaluate the potential antitumor activity of α-hederin, a monodesmosidic triterpenoid saponin isolated from Hedera helix, in human SW620 colon cancer cells stimulated with interleukin 6 (IL-6) for mimicking the tumor inflammatory microenvironment in vivo. Cell viability assay showed that IL-6 at 6.25 ng/ml significantly enhanced viability of SW620 cells, and thus this concentration was used to stimulate SW620 cells throughout this study. We observed that α-hederin concentration-dependently inhibited cell viability, migration and invasion in IL-6-treated SW620 cells. Moreover, α-hederin significantly restored IL-6-induced decrease in E-cadherin expression and abolished IL-6-induced increase in N-cadherin, vimentin, fibronectin, twist and snail at both mRNA and protein levels in SW620 cells. These data suggested that α-hederin suppressed IL-6-indcued EMT in colon cancer cells. Further molecular examinations showed that α-hederin inhibited phosphorylation of Janus Kinase 2 (JAK2) and Signal Transducer and Activator of Transcription 3(STAT3), and halted the nuclear translocation of phosphorylated STAT3 in IL-6-treated SW620 cells. In addition, JAK2/STAT3 signaling inhibitor AG490 not only produced similar inhibitory effects on EMT markers as α-hederin, but also synergistically enhanced α-hederins inhibitory effects on EMT markers in IL-6-treated SW620 cells. Altogether, we demonstrated that α-hederin suppressed IL-6-induced EMT associated with disruption of JAK2/STAT3 signaling in colon cancer cells. Our data strongly suggested α-hederin as a promising candidate for intervention of colon cancer and metastasis.

LC-MS/MS analysis and evaluation of the anti-inflammatory activity of components from BushenHuoxue decoction

Abstract Context: BushenHuoxue decoction (BSHXD) is a Chinese medicine prescription, which is composed of nine Chinese medical materials, used to treat osteoarthritis (OA). Objective: This study develops sensitive and convenient LC-MS/MS methods to analyze chemical components from BSHXD, and assess the anti-inflammatory activities thereof. Materials and methods: The chemical composition from BSHXD water extract was qualitative analyzed by high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (HPLC-ESI-Q-TOF-MS). Twelve reference compounds were analyzed by UPLC-ESI-MS/MS. Anti-inflammatory activities of target components were assessed by ELISA at 20 and 100 μg/mL. Results: It is the first time that 88 compounds were qualitatively identified from BSHXD, of which 12 with potential in treating OA according to the literature were quantified. Within BSHXD the contents of quercetin, isopsoralen, icarisideII, osthole, and isoimperatorin increased remarkably compared with those in single herb which make up BSHXD, the contents were 0.1999, 0.4634, 0.0928, 0.5364, and 0.1487 mg/g. ELISA data displayed that BSHXD and the five compounds mentioned inhibited the expressions of TNF-α, IL-6 and NO released from LPS-stimulated RAW264.7 cell, with maximum inhibition rates of 104.05% (osthole, 100 μg/mL), 100.03% (osthole, 100 μg/mL), and 93.46% (isopsoralen, 20 μg/mL), respectively. Discussion and conclusion: Content changes of 12 compounds in BSHXD and single herbs which comprise the prescription were measured and analyzed. Contents of five compounds increased may be explained by solubilization between drugs and chemical reaction. ELISA results reported that the increased contents of the five compounds could inhibit expression of the inflammatory factors.

Dalbergioidin Ameliorates Doxorubicin-Induced Renal Fibrosis by Suppressing the TGF-β Signal Pathway.

We investigated the effect of Dalbergioidin (DAL), a well-known natural product extracted from Uraria crinita, on doxorubicin- (DXR-) induced renal fibrosis in mice. The mice were pretreated for 7 days with DAL followed by a single injection of DXR (10 mg/kg) via the tail vein. Renal function was analyzed 5 weeks after DXR treatment. DXR caused nephrotoxicity. The symptoms of nephrotic syndrome were greatly improved after DAL treatment. The indices of renal fibrosis, the phosphorylation of Smad3, and the expression of alpha-smooth muscle actin (α-SMA), fibronectin, collagen III (Col III), E-cadherin, TGF-β, and Smad7 in response to DXR were all similarly modified by DAL. The present findings suggest that DAL improved the markers for kidney damage investigated in this model of DXR-induced experimental nephrotoxicity.

ONTD induces growth arrest and apoptosis of human hepatoma Bel-7402 cells though a peroxisome proliferator-activated receptor γ-dependent pathway

ONTD (3-Oxo-29-noroleana-1,9(11),12-trien-2,20-dicarbonitrile) is a novel synthetic derivative of glycyrrhetinic acid (GA), which has been reported to exhibit anti-inflammatory and anti-tumor activities through its mechanisms are not fully understood. Previously, we demonstrated that ONTD induces apoptosis of human hepatoma cells via a MAPK-dependent mitochondrial pathway. Recently, ONTD was found to increase sub-G1 accumulation and Annexin-V positive staining, indicating apoptotic induction effect. It was also be found that ONTD increase the PPAR-γ activity, reduce the phosphorylation of Akt and increase phosphatase and tensin homologue (PTEN) protein expression in hepatocellular carcinoma (HCC) Bel-7402 cells, and these were associated with the inhibition of cells proliferation. More importantly, these effects could be diminished by GW9662, a specific PPAR-γ antagonist, suggesting that ONTD can act as a ligand of PPAR-γ. Taken together, our novel observations suggested that ONTD may have potential implication in HCC prevention and treatment, and showed for the first time that the anti-tumor effect of ONTD may also be mediated through modulation of the PPAR-γ activation and mediated by the PTEN/Akt signaling pathway. The present study also supports ONTD as a potential drug candidate for chemoprevention or chemotherapy of HCC.

Dalbergioidin (DAL) protects MC3T3-E1 osteoblastic cells against H2O2-induced cell damage through activation of the PI3K/AKT/SMAD1 pathway

Reactive oxygen species (ROS) is a pivotal pathogenic factor in the development of osteoporosis. Dalbergioidin (DAL) can be isolated from Uraria crinite, an edible herb used as a natural food for childhood skeletal dysplasia. Recent research has implicated DAL as having an antiosteoporosis effect, although the mechanism of this is unclear. We used an effective oxidative stress model, induced by hydrogen peroxide (H2O2) in osteoblastic MC3T3-E1 cells, to investigate the protective effects of DAL in osteoporosis and the underlying molecular mechanisms. The results indicated that treatment with DAL maintained redox balance, reduced MC3T3-E1 cell apoptosis, improved alkaline phosphatase activity, and elevated the osteogenic-related protein expression of Runx2, Osterix, and BMP2 against oxidative damage induced by H2O2. The potential molecular mechanism involved in the protective effect of DAL against H2O2-induced cell death in MC3T3-E1 cells may lie in the activation of the PI3K/AKT/SMAD1 cell signal pathway. Taken together, the results indicated that the potential protective effects of DAL against osteoporosis were linked to a reduction in oxidative damage, suggesting that DAL may be useful in bone metabolism diseases, particularly osteoporosis.

Protective Effect of 2-Hydroxymethyl Anthraquinone from Hedyotis diffusa Willd in Lipopolysaccharide-Induced Acute Lung Injury Mediated by TLR4-NF-κB Pathway

Chronic inflammation and oxidant/antioxidant imbalance play a prominent role in inflammatory lung diseases. 2-Hydroxymethyl anthraquinone (HMA), an anthraquinone derivative found in Hedyotis diffusa Willd, has been reported to have broad-spectrum anti-inflammatory effects; the present study was conducted to investigate the protective effect of HMA in LPS-induced acute lung injury (ALI) and to explore its potential molecular mechanisms. The results showed that HMA remarkably attenuated LPS-induced pulmonary edema, myeloperoxidase activity, and inflammatory cytokine production. Besides, HMA showed significant antioxidative activity; it raised the levels of SOD and GSH and depleted the MDA level in serum of ALI mice. In vitro, HMA suppressed the production NO, TGF-β1, TNF-α, IL-6, and IL-1β in LPS-stimulated RAW 264.7 macrophage cells. The western blot analysis showed that TLR4 expression and the activation of NF-κB were antagonized by HMA. Moreover, addition of exogenous NF-κB inhibitor BAY11-7082 weakened the inhibitory effects of HMA in inflammatory cytokines and ROS production. Taken together, these findings provide the first experimental evidence supporting that HMA has protective effects on LPS-induced inflammation, which is mediated by TLR4-NF-κB pathway.

Fra-2 is a novel candidate drug target expressed in the podocytes of lupus nephritis

Lupus nephritis (LN) is a common and devastating complication caused by systemic lupus erythematosus. In this study, we evaluated the expression and mechanism of Fos-related antigen 2 (Fra-2) in LN. The results showed that Fra-2 was significantly increased in kidney biopsies of LN patients compared with healthy controls and other kidney disease in glomerular podocytes. The MRL/lpr mouse strain is a murine model of lupus, and it was used to study the mechanisms of Fra-2 in LN. The results showed that Fra-2 was expressed in the glomerular podocytes. We investigated the effects of inflammatory stimuli on Fra-2 protein expression in the glomerular podocytes, and found that interferon gamma was most effective at increasing Fra-2 protein expression. Knockdown of Fra-2 using siRNA enhanced the protein expression of nephrin. Therefore, Fra-2 may be a specific drug target for podocyte injury in LN.

-Hederin Arrests Cell Cycle at G2/M Checkpoint and Promotes Mitochondrial Apoptosis by Blocking Nuclear Factor-B Signaling in Colon Cancer Cells

Colon cancer represents the third most common malignancy worldwide. New drugs with high efficaciousness and safety for the treatment of colon cancer are urgently needed in clinical context. Here, we were aimed to evaluate the antitumor activity of the natural compound α-hederin in human colon cancer cells. We treated SW620 cells with interleukin-6 (IL-6) in vitro to mimic the paracrine inflammatory microenvironment of tumor cells. α-Hederin concentration dependently reduced the viability of IL-6-stimulated SW620 cells. α-Hederin increased the number of IL-6-stimulated SW620 cells at the G2/M phase and reduced the mRNA and protein expression of cyclin B1 and CDK1. Moreover, α-hederin induced apoptosis and loss of mitochondrial membrane potential in IL-6-stimulated SW620 cells. α-Hederin downregulated Bcl-2 expression, upregulated Bax expression, and promoted cytochrome c release from mitochondria into cytoplasm. Additionally, α-hederin elevated the levels of cleaved-caspase-9, cleaved-caspase-3, and cleaved-PARP, but had little effects on the levels of cleaved-caspase-8. Moreover, α-hederin prevented the nuclear translocation of nuclear factor-κB (NF-κB) and reduced the phosphorylation of IκBα and IKKα, suggesting the blockade of NF-κB signaling. NF-κB inhibitor PDTC not only produced similar proapoptotic effects on IL-6-stimulated SW620 cells as α-hederin did, but also synergistically enhanced α-hederins proapoptotic effects. Furthermore, α-hederin inhibited the phosphorylation of ERK in IL-6-stimulated SW620 cells, which was involved in α-hederin blockade of NF-κB nuclear translocation. Altogether, α-hederin suppressed viability, induced G2/M cell cycle arrest, and stimulated mitochondrial and caspase-dependent apoptosis in colon cancer cells, which were associated with disruption of NF-κB and ERK pathways, suggesting α-hederin as a promising candidate for intervention of colon cancer.